Van Schalkwyk was South Africa's former minister for environmental affairs and tourism until May 2009, when the ministry was split. He succeeded former South African president FW de Klerk as leader of the National party in 1997 and presided over its dissolution and merger with the ruling African National Congress in 2005.

De Boer and others have stated that a binding global deal to tackle climate change will not be reached this year at the main annual UNFCCC event in December. That elevates the importance of the 2011 meeting, which will be held in South Africa, perhaps boosting van Schalkwyk's chances.

But there will be other candidates. Reports from India suggest that the environment minister, Jairam Ramesh, is supporting the candidacy of environment secretary, Vijai Sharma, who is also said to have the support of China. Alongside Brazil, India, China and South Africa - also known as the Basic group of nations - were seen to be the key drivers behind the Copenhagen accord, the weak agreement that emerged from the last UN climate summit in December.

The appointment is made by the UN secretary-general, Ban Ki-Moon, from a private shortlist, which he discusses with representatives from around the world.

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